The embodiments described herein relate generally to motors, and more particularly, to systems and methods for controlling an electric motor.
Electric motors are used in a variety of systems operating in a variety of industries. Some such uses of electric motors include evaporator and/or cold-storage applications such as walk-in freezers. Electric motors used in such applications are exposed to freezing temperatures, for example, temperatures as low as −50° C. At such temperatures, a large amount of condensing occurs, including continuous heating and cooling during different phases throughout the day. In some instances, an internal ambient temperature of the electric motor may reach a freezing point and ice may form within the motor's components, resulting in a potential locking environment. Moreover, if any ice formation is defrosted too rapidly, damming and/or flooding may occur and damage the electric motor. In other instances, high winds may create a windmilling effect or reverse rotation of a fan coupled to the electric motor. This reverse rotation may create a load with large inertia that can become large enough to prevent the motor from starting and/or may damage the components of the electric motor.